Fix text cutting off when printing and differences between clicking print and doing ctrl + P

[GVodyanov]

Fix #9853

Previously for printing all we did was hide unnecessary DOM elements with CSS

What this PR actually does:

• distinguish between printing singular messages (through the actions menu) and printing the whole thread with Ctrl + P
• If printing a specific message only the iframe is printed, with thread info injected up top
• If printing a whole thread with Ctrl + P some DOM elements are hidden with CSS, and some are removed forcefully with javascript. This is needed because browser printing APIs aren't the best, and even hidden elements mess up the layout with Chrome. The downside of this is that the browser cannot read elements inside of iframes, so text and images are split between multiple pages. After this is done the page has to be reloaded to restore the deleted elements.
• Fix bug related to the print content being narrow in Firefox, this was caused by the actions menu still existing in the DOM even if hidden for a few seconds after being closed
• Update iframe-resizer to version 5: now it split between two libraries, child and parent
• Handle printing of plain text messages by creating an iframe and inserting them into it

[GVodyanov]

Note: narrow messages in firefox seem to reproducible only after having clicked the menu buttons in the thread element, even though the menu was subsequently closed..?